Ad Support : Nano Technology Netbook Technology News Computer Software
By drilling a tiny pore just a few-nanometers in diameter, called a nanopore, in the graphene membrane, they were able to measure exchange of ions through the pore and demonstrated that a long DNA molecule can be pulled through the graphene nanopore just as a thread is pulled through the eye of a needle.
“By measuring the flow of ions passing through a nanopore drilled in graphene we have demonstrated that the thickness of graphene immersed in liquid is less then 1 nm thick, or many times thinner than the very thin membrane which separates a single animal or human cell from its surrounding environment,” says lead author Slaven Garaj, a Research Associate in the Department of Physics at Harvard. “This makes graphene the thinnest membrane able to separate two liquid compartments from each other. The thickness of the membrane was determined by its interaction with water molecules and ions.”
Graphene, the strongest material known, has other advantages. Most importantly, it is electrically conductive.
“Although the membrane prevents ions and water from flowing through it, the graphene membrane can attract different ions and other chemicals to its two atomically close surfaces. This affects graphene’s electrical conductivity and could be used for chemical sensing,” says co-author Jene Golovchenko, Rumford Professor of Physics and Gordon McKay Professor of Applied Physics at Harvard, whose pioneering work started the field of artificial nanopores in solid-state membranes.
“I believe the atomic thickness of the graphene makes it a novel electrical device that will offer new insights into the physics of surface processes and lead to a wide range of practical application, including chemical sensing and detection of single molecules.”
The graphene was stretched over a silicon-based frame, and inserted between two separate liquid reservoirs. An electrical voltage applied between the reservoirs pushed the ions towards graphene membrane. When a nanopore was drilled through the membrane, this voltage channeled the flow of ions through the pore and registered as an electrical current signal.
When the researchers added long DNA chains in the liquid, they were electrically pulled one by one through the graphene nanopore. As the DNA molecule threads the nanopore, it blocks the flow of ions, resulting in a characteristic electrical signal that reflects the size and conformation of the DNA molecule.
If you liked this article, please give it a quick review on Reddit, or StumbleUpon. Thanks
Supporting Advertising
Business Success
How to Make Money
Executive Jobs
Paid Surveys
Thank You
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
Known for identifying cutting edge technologies, he is currently a Co-Founder of a startup and fundraiser for high potential early-stage companies. He is the Head of Research for Allocations for deep technology investments and an Angel Investor at Space Angels.
A frequent speaker at corporations, he has been a TEDx speaker, a Singularity University speaker and guest at numerous interviews for radio and podcasts. He is open to public speaking and advising engagements.